When a quick barbecue device is used, a lower heating plate and a magnetron are arranged below a cooking cavity and immobilized, the position of an upper heating plate can be adjusted according to the height of food so that the heating plate is in contact with the food or kept a short distance from the food, and an upper heating plate adjusting device in the prior art is locked at different positions via a positioning pin to adjust the distance between the heating plate and the food. However, in the prior art, the height of the heating plate can only be set at several fixed positions, and the position of the upper heating plate cannot be continuously set, so that the requirement for accurately positioning the heating distance of food having different heights cannot be met. Furthermore, in the existing structure, when the height of the heating plate is adjusted, the positioning pin needs to be unscrewed by means of a tool and then mounted into another positioning hole, so that the operation is complex and long time is needed. Besides, by adopting the existing adjusting device, after the height of the heating plate is adjusted, a user cannot know the food accommodating height of the cooking cavity, so that the user cannot accurately adjust the height mounting position of the upper heating plate according to the height of the food, and the user experience is poor.
Therefore, the problem to be solved at present is how to provide a cooking appliance such as a quick barbecue device which can allow the height of an upper heating plate to be adjusted simply, quickly and continuously and display the food accommodating height of a cooking cavity.